The M5 was closed between Junction 26 and Junction 27, the junction with the A361 North Devon link road, for several hours yesterday following a crash.
The northbound carriageway was closed for around two hours and tailbacks reached all the way to Cullompton, after a car crashed and ended up on its roof. The crash was reported to the emergency services at 4.53pm.
The Devon Air Ambulance landed at the scene, although all five occupants of the 4x4 vehicle were able to free themselves from the car after it crashed.
They were all taken to hospital by land and air ambulance after receiving treatment at the scene from paramedics and firefighters.
A Devon and Cornwall police spokesman said it was not known what caused the vehicle to overturn and said Avon and Somerset police was dealing with the scene of the crash.
Witnesses at the scene took to Twitter to describe the crash.
Debbie Clifford drove past the crash, which happened approximately three miles south of Junction 26.
She tweeted: "When I hear that a car's overturned I think it's just rolled over not that it's spun through the air at 80mph like the crash behind me.
"Saw the cloud of dust as the collision happened then this green car just hurtled at me. Absolutely terrifying."
She also described the crash as "like something out of a film".
A diversion was put in place between Tiverton and Wellington using the A38, before the M5 reopened at around 7pm.